1. Field of the Invention
The present invention relates to fiber optic terminators/connectors, and more particularly to a high density fiber terminator/connector.
2. Description of the Related Art
Common fiber optic terminations/connectors terminate one fiber at a time. There are several connector styles (e.g., FC/PC, LC), but in all cases, a single fiber is inserted and glued in a precision ferrule, which is typically made of ceramic. The end of the ferrule and fiber are polished together to provide a smooth surface or a desired shape.
When multiple fibers are connected together, each fiber is terminated with an FC/PC connector as described, and the fibers are connected together one pair at a time. This process is extremely time-consuming and costly when connecting a large number of fibers together.
State of the art high density fiber connectors use micromachined v-grooves in which the fibers are located in v-shaped channels. This technology results in linear arrays of fibers, where the relative positioning of the fibers is limited by the fabrication precision (or imprecision) of the fiber v-grooves and by a diameter uniformity (or non-uniformity) of the fibers. When v-grooves are stacked to provide two-dimensional arrays of fibers, the relative position accuracy is further reduced and results in increased insertion loss in the connection of two such arrays.
A high density fiber terminator/connector and methods of making the high density fiber terminator/connector are provided in accordance with the present invention. One method uses silicon micro-machining to terminate multiple fibers simultaneously. This simplifies the process and improves the alignment of connecting multiple fibers together or positioning multiple fibers together to free-space optical elements.
One method uses Deep Reactive Ion Etching (DRIE) to make precise holes in a silicon wafer. The holes in the silicon may be arranged in any desired pattern by using, for example, a mask fabrication process with electron-beam writing of the mask, such as photolithography masking. A single photolithographic mask provides extremely high precision location positioning, and the relative position of each fiber in the holes can be accurately controlled. The accuracy in the relative positioning of the fibers ensures that all fibers are simultaneously aligned. Thus, photolithographic masking and deep reactive ion etching enable the fabrication of connectors for a plurality of fibers. Photolithographic masking and deep reactive ion etching also allow multiple fibers to be accurately aligned to free-space optical components.
One aspect of the invention relates to a method of making an optical fiber terminator. The method comprises using deep reactive ion etching to etch a plurality of holes in a silicon substrate, wherein each hole is sized to fit an optical fiber; and placing an optical fiber in at least one hole.
Another aspect of the invention relates to an optical fiber terminator in an optical switch. The optical fiber terminator comprises a silicon substrate with a plurality of holes formed by deep reactive ion etching, wherein each hole is sized to fit an optical fiber.
Another aspect of the invention relates to an optical fiber terminator with holes formed to allow insertion of fibers at an angle with respect to the substrate surface.
Another aspect of the invention relates to a method of making an optical fiber terminator. The method comprises etching a plurality of holes in a silicon substrate, wherein each hole is sized to fit an optical fiber; forming a plurality of flaps in the substrate around each hole, the flaps being configured for kinematic alignment of an optical fiber in each hole; and placing an optical fiber in at least one hole.
Another aspect of the invention relates to an optical fiber terminator, which comprises a silicon substrate. The silicon substrate comprises a plurality of holes etched in the silicon substrate, wherein each hole is sized to fit an optical fiber. The silicon substrate also comprises a plurality of flaps formed in the substrate around each hole. The flaps are configured for kinematic alignment of an optical fiber in each hole.